Commit Message

The attached patch fixes
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79916
The PR is about LRA cycling on some tests when SD data are used. The
problem was in that actual assigned reg to pseudo was not in the pseudo
preferred class and this resulted in wrong generated code which LRA
tried to change again and again.
The patch was successfully bootstrapped and tested on ppc64 (gcc110).
Is it ok to commit?